Crosslinkable Langmuir-Blodgett films with conjugated polymers: Optical characterization and use in devices

We report a study on Langmuir-Blodgett (LB) films of poly(3-hexylthiophene) (PUT) in a crosslinkable matrix of linoleic acid (LA). Optical absorption studies at elevated temperatures indicated that the structure of PHT/LA films is stable even up to 460 K. The films were used to fabricate light-emitting diodes (LEDs), showing emission at about 2.0 eV and a quantum efficiency approaching 0.01%. The stability tests indicated that the lifetime of the best PHT/LA LEDs was about three orders of magnitude higher than that of reference LEDs using an arachidic acid matrix.